I had something quite similar last week with my 1M. It has 14.000Km, and I've been using it for short trips the last few weeks. Last week i decided to take the 1M to a track day at Spa - Francorchamps. It's about a 250 Km drive from where i live.
So before i set of i checked the oil level and it was at max. So i set off.
About 200 Km down the road at normal driving speeds i suddenly got a orange warning the oil level was at min and i had to add 1L of oil.
At 5 Km from the entrance of the track the warning turned into a red warning stating to add oil immediately.
So how could I've burned more than 1 L of oil on 250Km of normal highway driving.
I decided to drive to the track and we added 1L of oil. Let the engine run for a few minutes and the e-dipstick was in the middle. So we decided to add another 1/2L of oil. The strange thing is this last /2 L of oil never showed in the oil level!. We let the engine run for 20 min or more, and still the oil level never raised above the level before adding the 1/2 L.
I decided to start driving at the track since it was above minimum. After a while of fun at the track ( did about 5 stints of 30 mins) the oil level was still at the middle of the oil meter..
Strange thing happened when i got home ( after 250 Km of normal high way driving). The oil level was back at maximum.
So the 1/2 L of oil was lost during 2.5 hours of track driving, and showed up when i got home.
After reading the technical info in this thread, i understand there must have been moisture in the engine oil before i set of to the track so the measurement was at maximum, while in reality there wasn't enough oil in the engine. Only after a long drive the measurement was correct.
So if i didn't go to the track, i might have been driving with an engine low on oil and never would have known.
Coclusion: Take your 1M to track every few months
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Picure at the famous curve Eau Rouge- Raidillion: